On Fri, Dec 5, 2008 at 2:28 AM, Cai, Xin <[EMAIL PROTECTED]> wrote: > hi guys > So I have been playing around with AV library for a few days and so far I > gotten it to grab video from an IP camera and convert it to mpeg4 and write > it to the disk. > My code basically works by > 1. grab frame from Video and decode it by calling avcodec_decode_video > 2. encode the frame by calling avcodec_encode_video > 3. write the frame to disk using av_write_frame > > Now I want to be able to further control the quality of the video I am > writing to the disk. So I would like to know how can I change the frame rate > of the video being written to the disk? Now base on the output_example.c > file I thought that it is controlled > by the AVstream *st->codec->time_base.den field. But when I tried to set > that, all it did is slow down the rate in which the video is being played > at. So lets say I have a 5 second video at 30 fps, now it plays it at 2fps > but it takes 15 * 5 seconds to finish playing. So how can I get it to drop > frames? > > My second question is, I also want to be able to strip away color > information and turn the video to black and white. How would I do that? > Thanks >
use swscale to convert decompressed video from their pix_fmt (probably RGB32 or YUV420P) to a grayscale format > > Xin Cai > > > > > > _______________________________________________ > libav-user mailing list > [email protected] > https://lists.mplayerhq.hu/mailman/listinfo/libav-user > _______________________________________________ libav-user mailing list [email protected] https://lists.mplayerhq.hu/mailman/listinfo/libav-user
